1. Field
Exemplary embodiments of the invention relate to an atomic layer deposition apparatus, and more particularly to an atomic layer deposition apparatus which forms an atomic layer in the form of a fine thin film on a substrate.
2. Description of the Prior Art
A gas injection device of an atomic layer deposition apparatus typically includes injection nozzles for injecting multiple reaction gases and purge gas nozzles provided between the injection nozzles to prevent foreign substances from being generated due to unwanted reactions between the reaction gases.
In general, to deposit a thin film having a predetermined thickness on a substrate, such as a semiconductor wafer or glass, a thin film fabrication method using a steam method, a chemical vapor deposition method, or an atomic layer deposition method is used. Among such deposition methods, the atomic layer deposition method is a method for stacking respective reactants on a processed substrate in the unit of an atomic layer by successively supplying reaction gases and purge gases through a gas pulsing method.
The atomic layer deposition method is typically used to form a thin film having a high aspect ratio to increase integrity of a semiconductor device, for thin film uniformity on uneven surfaces, and to improve electrical and physical properties. According to the atomic layer deposition method, reactants are dissolved by chemical replacements through a periodic supply of reaction gases rather than incineration to provide a stoichiometric film with high film density. Since residual products produced due to the chemical replacements in the process are always gases, the residual products may be efficiently removed to facilitate cleaning of a chamber. Further, since only temperature is a process parameter, the process adjustment and maintenance may be easily performed. However, it typically takes a relatively long time to form a desired thin film over the whole region of the substrate using the atomic layer deposition apparatus in comparison to other deposition apparatuses.